This invention relates to a sequential ignition system for an oxygen generation device including a plurality of oxygen generation elements, and more particularly to such a system for automatically burning a plurality of oxygen generation elements one by one or a predetermined number greater than one at a time so as not to interrupt the generation of oxygen, and without burning all the oxygen generation elements at a time.
For a long time, there have been known portable, safe oxygen sources formed of the chemical oxygen generation element including principally alkali metal chlorate, for example, sodium chlorate added with an exothermic agent such as a powder of reduced iron and a chlorine absorbent such as barium perioxide and shaped into a candle. Such a chemical oxygen generation element is called a "chlorate candle" and there have been previously proposed a variety of oxygen generation devices employing the chlorate candle. The chemical oxygen generation element has many advantages, on the one hand, but some disadvantages, on the other hand. For example, the chlorate candle decomposition rate is difficult to control and therefore rate of oxygen generation can become erratic. One result has been that large-sized oxygen generation elements have been especially difficult to maintain at a rate at which oxygen is stably generated. Accordingly, if it is demanded to generate oxygen in the stabilized manner for a long time interval then it has been generally adopted to prepare a plurality of oxygen generation elements and sequentially burn them one after another or a predetermined number greater than one at a time. Under these circumstances, when any oxygen generation element being burnt has completed or nearly completed generating oxygen, the next succeeding one must be immediately ignited thereby to prevent the generation of oxygen from interrupting. To this end, a variety of sequential ignition systems for the group of oxygen generation elements are devised. Since oxygen generation devices of the type referred to are frequently employed in case of emergency, they are desirable to be as simple in both construction and manipulation as possible and still reliably operated.
Accordingly it is an object of the present invention to provide a new and improved system for sequentially igniting a plurality of oxygen generation elements with a simple, reliable construction.